The dakine ones that allow feet to go in either way. Attach them straight and then duck your foot to lock in. This has many purposes. Boardspinning not locked to full rotations can stop at 180 360 540 whatever. Safety you spin your foot straight and come out easy but turn to lock. Leash pulling board towards you , you don't have to look which way to put on just put on cause it will be right. SYMETRICAL BOARD.